Previous research has showed that crack cocaine dependencies frequently associated with engagement in sex exchange for drugs and/or money. Cultural, social and economical factors make female crack cocaine users particularly vulnerable to such practices and, as a consequence, to increased risk for HIV. The escalation of the AIDS epidemic among crack cocaine abusing women justifies the need for research to better understand the mechanism underlying the relationship between crack cocaine abuse and sex trade. This association raises the paradox of voluntarily self-destructive, even life-threatening behaviors. The challenge is to understand why people continue to engage in such behaviors that they know will harm them, despite their attempts not to do so. The proposed research suggests that one mechanism responsible for such paradox is the dissociation between the explicit and implicit evaluations and behavioral intentions regarding engagement in sex trade in the context of drug use. Specifically, while crack cocaine users may report negative feelings toward sex trade and behavioral intentions to avoid it in the future, on the implicit level, such practice remains positively related to the goal of obtaining the drug. Consequently, once such goal is activated by contextual factors (though a cue-conditioned craving), this activation will automatically activate behavioral representations and resultant action (tendency to engage in sex trade) enabling the goal directed behavior to occur in the absence of conscious intentions and control. The proposed research aims to investigate the operation of such mechanism in a sample of 120 crack cocaine users currently enrolled in residential substance abuse treatment as a function of gender (female vs. male), previous involvement in sex exchange (present vs. absent) and cognitively induced drug craving (present vs. absent). The research adopts a theoretical and methodological approach that emphasizes motivation as cognition and its implicit nature. Such approach offers a conceptual background and specific investigation techniques to asses those processes underlying the relationship between crack/cocaine abuse and risky sexual behavior that may not be readily captured by conscious introspection or cannot easily be controlled, but they nevertheless influence behavior. Empirical support for such mechanism may inform existing interventions which could help to moderate these automatic mechanisms. In addition, new techniques aimed directly at modifying implicit cognitive processes (e .g. through evaluative conditioning) in substance abuse may be developed.